DETROIT -- The clock will reset when Andy Dirks resumes his rehabilitation assignment. But the Detroit Tigers don't expect that he will be starting from scratch.

The Tigers announced Thursday morning that Dirks will resume his rehabilitation assignment Friday with Single-A West Michigan. Position players are limited to 20 days on a rehabilitation assignment, but the clock will reset since it has been more than five days since the Tigers pulled him off his most recent rehab stint.

"It's certainly nothing like when he restarted initially," Ausmus said. "He's not starting from ground level again, for sure."

Dirks has been on the disabled list all season after undergoing back surgery in March. The Tigers initially said they expected him to return in early June, but now it seems likely it will be mid-August.

In fact, once Dirks is ready to go, the Tigers could choose to simply option him to Triple-A Toledo until rosters expand on Sept. 1 rather than putting Don Kelly through the waiver process or demoting J.D. Martinez, who has options remaining but has been an important part of the offense this season.

Dirks will likely spend some time with the Mud Hens on his current rehabilitation assignment. West Michigan is playing at home through Sunday and then won't be back home until Aug. 12. Toledo plays in Indianapolis for four games Saturday through Tuesday and then starts a 10-game homestand on Aug. 7.

The Whitecaps announced that Dirks is expected to remain with them for six games, three at home this weekend and three next week on the road at Lake County. That would line Dirks up to join the Mud Hens when they start their homestand on Aug. 7.